McCain's office declined to comment to Business Insider on
Trump's attack.

However one of McCain's top allies blasted Trump in response.
Mark Salter, McCain's former chief of staff and coauthor,
wrote the following on Facebook, according to a tipster:

Donald Trump isn't just an embarrassment to the Republican Party,
or to whatever percentage of unserious self-identified
Republicans say they would vote for him. He's an embarrassment to
the country. He possesses all the traits snobbish foreigners
deride Americans for. He's bumptious, narcissistic, obtuse and
full of it. You'd think he was a Brit actor playing an American
on the BBC. GOP presidential candidates who can't find the nerve
to criticize the guy ought to grow a pair. You'll have done
America a good turn, and you'll feel better about yourself.